Stoker



o. E. BoRNHAUsER STQKER Filegi July 17,1935 2 sheets-sheeti 1 0770 5.-- BORM/H055?.

Nov. 17, 1936.

O. E. BORNHAUSER STOKER Filed Jly 17,' 1955 2 sheets-shei 2 Patented Nov. 17, 1936 PATENT OFFICE 2,061,450 t e s'roKEa Otto E. Bornhauser, Sandusky, Ohio, assignor to The Her-Born Engineering and Manufacturing Company, Sandusky, Ohio, alcorporation Application July 17, 1933, Serial No. 680,854

1 Claim.

This invention relates to apparatus for feeding fuel to a fire and for occasioning the distribution of the fuel over the zone of combustion. Particularly, the invention relates to a stoker especially adapted for use in conjunction-with large furnacessuch as those ordinarily found in power plants, factories, and large apartment or oice buildings for heating the `boilers of the steaml generatingl systems.` However, itis to be understood that my stoker is not limited in its use to the specific application just mentioned, but may be employed in dwellings for attendingk to the furnace as well.

The aim of this invention is to provide a mechanical stoker by virtue of which a wide spread distribution of fuel is obtainedin thecombustion zone which insures greater efficiency in the burning of the fuel with a consequent low percentage of waste products of combustion and maximum securing of heat energy. On the other hand,'it is also my aim to provide an apparatus that will necessitate a minimum of manual intervention during operation and will have a lowupkeep cost, which is an important factor that influences the desirability of the apparatus.

Essentially, the apparatus incorporates a plurality ofA what I choose to term fluid fingers which areyin effect, streams of air or steam that arev directed downwardly into the combustion zone from a point oset to one side of the Zone. Fuel, which is preferably in the nature of powdered coal or finely divided steam coal, is gravity-fed into the Zone of the fluid fingers and onto Other objects and advantageous features of this invention are to be observed in the following detailed description and accompanying draw` ings, wherein like characters of reference indicate like parts, and wherein'- Figure 1 is afragmentary View of a boiler furnace showing the nature and arrangement of my stoking apparatus with relation thereto, said apparatus being shown in section.

' Figure v2 is a fragmentary detail and transverse section of a slightly modiedform of blower unit...

(el. 'n0-104) Figure 3 is a top plan view of the blower housing unit illustrating the nature and arrangement of'the'fluid ports.

Figure 4 is afront elevation of the blower unitv taken on the Yline 4 4 of Figure 3.

Figure 5 is a top plan view of a modified form of blower unit.

Figure 6 is a section taken on the line 6-'6 of Figure 5." Y

With reference to the drawings, I have shown 10 my novel stoker as employed in conjunction with a boiler furnace which may be identified as havingfa front wall A of the usual construction such as fire-brick or other refractory materials. This wall formsl one conne'of a fire bowl or combus- 15 tion chamber Bhaving the usual grate bars C in' the lower zone thereof which are accessible from the outside through the usual door D.

To accommodate my apparatus, the upper zone of the wall A, shown in Figure l, is fashioned 20 toprovide a downwardly inclined channel I that widens in area at its lower end and opens into the'combustion chamber. The upper zone of the channel is intended to accommodate a fuel chute 2, hereinafter referred to, whereas the lower Zone 25 is intended to accommodate what I choose to term the blower unit of my apparatus. 'I'he fluid supply pipe 3 is also brought in through the end wall of the furnace and is threaded into the blower unitk as will be hereinafter referred to. v3() As shown in Figure l, mynovel blower unit is shownas comprising a body portion 4 which preferably takes the shape shown in Figures 3 and 4. This body portion is further provided with an in- K terior l'chamber 5 adapted to receive a fluid such 35 as steam or compressed air through the port 6 which communicates. with a source offluid supply through the pipe 3 which is valved as at l to control the passage of4 fluid thereto.

As hereinbefore stated, it is my intention to feed 40 the fuel by gravity to the blower unit and to deflect the fuel from its original path of travel into the combustion Zone B of the furnace. To accomplish this, I provide on the blower unit, sur-r faces that will serve to direct and guide the stream 45 of fuel` in conjunction with ythe fluid blast for forciblyejecting the said fuel to the fire bowl. To this end I` have provided a plurality of ports 8, as best shown in Figure 3, thatcommunicate with the chamber 5 and are directed voutwardly over 50 a spade-shaped deiiecting member 9, Figures l, 3, and ll, that is formed as an integral part of the housing and extends outwardly therefrom. These ports 8 are arranged as radii about a common center l0, Figure 3, and tend to direct a scavenging 55 fluid flow over the top surface of the member 9 to blow off the particles of fuel that may be deposited thereon.

The blower unit is additionally provided with a surface I I that overlies the ports 8 and is angularly disposed with relation thereto and with relation to the deflecting member 9. Surface II is a substantial extension of the bottom surface of the chute 2 to present an inclined path over which the fuel may freely travel into the zone of the air fingers. To accommodate the lower end of the chute 2, the surface of the unit is oset inwardly to provide a niche I2 against which the lower end abuts.

In Figure 2, the blower unit is of generally thesame construction as hereinbefore described with relation to Figures 1, 3, and 4, excepting that the base or bottom wall of the niche or recess I2a has a slightly different angular relation to surface I Ia, as compared with the corresponding elements I2 and II respectively, in Figures 1 and 3. For convenience, the'elements of the Figure 2 unit which are similar to the elements of the -unit of Figures 1, 3, and 4, are designated by the same reference characters with the exponent a. The mounting of thevmodified blower unit of Figure 2 in the furnace is more particularly referred to hereinafter.

vAssuming now that the furnace wall A has been properly formed to receive the various parts of thisapparatus, the blower unit may be placed therein in the position shown in Figure 1 with the forwardend of the member 9 lying on the bottom of the channel I. The rear end of the unit is elevated through engagement with one of lthe fire brick as shown so that approximately a straight path is afforded to the fuel in a downwardly angling direction toward the zone of the fluid fingers. When the valve'l is open, air or steam under pressure flows through the ports 8 and outwardly over the surface of the member 9 which is thereby scavenged of all the fuel being deposited thereon which is in turn blown over into the combustion chamber where it is consumed. In this manner the fuel will be afforded a wide spread distribution over the combustion zone with consequent increase in efficiency in the burning thereof;

In some types of furnace the relation between the combustion chamber andthe fuel feed inlet is such vthat the blower unit would not operate advantageously if placed in a position shown in Figure l, andaccordingly, the blower may be placed on the floor of the channel in the position shown in Figure 2. Now this positioning of the blower unit occasions a slight rearrangement in the support for the lower end of the chute 2a in this mannen-the upstanding wall of the niche I2a is substantially normal to the surface I Ia and the bottom surface of the niche is substantially parallel to the surface IIa, although in a lower plane, so that the lower end of the chute will seat properly and firmly in engagement with the cooperating surfaces on the blower. Hence, a substantially `straight'path is afforded from the point of entry of fuel into the discharge chute 2a to the surface of the plate 9a whereas, in Figure 1 there is a slight angle in the path, in the zone of the blower. Accordingly, when the blower unit rests on the bottom of the channel I, the deflecting surface 9a, instead of being downwardly canted into the zone of combustion, lies substantially normal to the vertical axis of the combustion chamber. The fuel will be efficiently discharged, nevertheless, by virtue of the fluid blast from rthe ports 8a.

In Figure 5, I have shown a slightly modified form of blower unit that is intended to overcome a certain feature, which cannot be termed objectionable, but which, for some reason or other, might not appeal to engineers. By this I mean that the fuel traversing the chute may have a tendency to pile up on the deflecting plate 9b in certain zones between the air fingers. To overcome this, the modification as shown` at Figure 5 is produced with a plurality of ridges 20 that project upwardly from the spade-shaped deflecting member 9b, lying in spaced relation and extending from the marginal confine of the plate rearwardly to the body portion of the blower. It is to be observed that these ridges terminate, at their inner ends, between the air ports 8b so that, in effect, each air port is directed into a channel formed by two spaced ridges and a floor portion 2 I Figure 6, inclined to the horizontal, as shown. In this way, all material falling on the plate and seeking out the bottom-most level of the floor 2 I will be in substantial alignment with the fiuid flow andthe piling up of fuel will be overcome.

It is also to be observed that these ridges are slightly curved in the direction of their length toward the outer marginal edges of the spadeshaped plate 9b on eitherside of the longitudinal center line of the device. Hence, with the arrangement just detailed, I will afford a complete scavenging of the surface of the plate 9b receiving fuel, Viz; surfaces between the ridges and the surfaces between the outermost ridges and the marginal edges of the plate, which are also inclined toward the centerof the plate as shown in Figure 6. In all other respects this blower unit is identical with the unit shown in Figures 1 and 2 and is intended for installation wherever such blower units may be installed.

It is to be observed that I am able to vary the rate at which fuel is fed to the combustion chamber by virtue of the hand valve I which controls the fluid under pressure, and by the same token to vary the feeding of the fuel to the zone of combustion. It is a known fact that a blower will create a forced draught to thereby accelerate the rate of combustion. It may therefore be said that I provide a means in the form of the hand valve I for varying the rate of combustion as well as the rate 0f feed. It may be fur- .ther stated that I vary the distribution of the fuel as well as the rate of combustion. This4 is extremely advantageousrsince. I reduce the necessity for manual interventionv in controlling the rate of feed, the distribution of the fuel, and the rate of combustion, all from a single source.

Having thus described my invention, what I claim as new and` desire to secure by Letters Pat,- ent of the United States, is

In a stoking device of the class described, a unitary fuel guide and distributor comprising a hollow body, the upper surface of which presents an inclined fuel receiving and guiding area of substantial extent and over which fuel deposited thereon directly passes by the action of gravity, said upper surface being provided with a fuel chute receiving recess having a forward wall constituting an abutment shoulder for engagement with the rear end of the chute to support the latter, and abottom wall defining the angle of disposition of the fuel chute in its cooperation with the guide and distributor unit in directing fuel to the latter by gravity, said hollow body defining within the same a fluid chamber, and having afluid inlet passageand outlet passages communicating with said chamber, said outlet passages extending through the walls of said body adjacent the lower portion of the fuel receiving and guiding area aforesaid, said body being further provided with an integral plate extending rearward therefrom and having a surface of substantial area serving to receive fuel from said aforementioned inclined surface in advance of said uid outlet ports and from which latter surface fuel deposited thereon is discharged into the combustion chamber of a furnace by a uid medium directed into the fluid chamber under pressure.

OT'IO E. BORNHAUSER. 

